A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateTrusted ADU Builders for Riverside Homeowners
Adding an accessory dwelling unit (ADU) – a separate, fully equipped living space on your existing property – is one of the smartest ways to add square footage, rental income, or a home for aging parents without buying new land. In Riverside, permits, setbacks, and the city’s ADU ordinance can stall a project before it even breaks ground. Lodgewick ADU Riverside has built ADUs, garage conversions, and home additions across the Inland Empire since 2010 - including projects by our ADU Builders in Riverside, and we put every price, every timeline, and every guarantee in writing before work begins. If you’re wondering whether your Riverside lot can support a detached unit, a JADU, or a garage conversion, call (831) 292-4191 for a free, no-pressure estimate. Russ Delmar, who leads our Riverside team, will walk you through what’s possible on your specific property.
ADU Construction
ADU Construction is the full build-out of a secondary dwelling unit on a residential lot – from foundation and framing through electrical, plumbing, drywall, and finishes. You need it when a prefab shell won’t fit your setback constraints, when Riverside’s hillside lots demand custom engineering, or when you want a unit that matches your main house’s architecture. Lodgewick ADU Riverside handles the entire construction process, including permits, inspections, and closeout documentation. A ground-up custom ADU in Riverside typically runs $250,000 to $450,000 depending on site conditions, utility runs, and finish level. We write that number down before the first shovel hits dirt, and it does not change at the door.
Foundation and Utility Work
Riverside’s older neighborhoods – Wood Streets, Magnolia Center, parts of Arlington – often have dated sewer laterals and undersized electrical panels. We include those upgrade costs in your written estimate up front, not as a surprise change order later. Our crews trench, run conduit, and pour foundations according to the approved plan and Riverside’s current building code, and we bring the same expertise to projects handled by our ADU Builders in Rialto.
Rough-In to Finish
Once the shell is up, we move through framing inspection, electrical, plumbing, insulation, drywall, and finishes. Your project gets a defined arrival window for every phase, and the job site is cleaned at the end of each day. That’s The Kingswell Way, and it’s written into every contract.
Detached ADU
A Detached ADU is a standalone structure – separate from the main house – with its own entrance, kitchen, bath, and utility connections. Riverside homeowners choose this route when they want maximum privacy for a tenant, a quiet space for an in-law, or a rental unit that feels like its own address. Lodgewick ADU Riverside designs and builds detached units from 400 to 1,200 square feet, and we also install high-quality prefab options from manufacturers like Abodu and Cover when the lot’s access and setbacks allow. A detached ADU in Riverside generally costs $180,000 to $400,000 all-in, with prefab units landing on the lower end and custom builds on the upper end.
Setback and Lot Coverage
Riverside’s ADU ordinance allows detached units up to certain height and lot-coverage limits depending on your zoning district. We pull your parcel’s specific requirements and design around them, so you don’t pay for a plan that gets rejected. Canyon crest and hillside lots in particular require careful slope and drainage planning - a challenge our ADU Builders in Fontana know well too.
Prefab vs. Custom Build
Prefab units from Abodu and Cover can cut construction time significantly because the modules are built off-site. Custom builds take longer but give you complete control over layout and finish. We’ll show you both options with real price tags, then you decide.
JADU
A JADU – junior accessory dwelling unit – is a smaller conversion within the existing footprint of your home, typically a spare bedroom, attached garage, or basement turned into a compact living space with a kitchenette and separate entrance. It’s the most cost-effective path to rental income or a private suite. Lodgewick ADU Riverside builds JADUs that meet California’s 500-square-foot maximum and Riverside’s owner-occupancy requirements. JADU conversion costs in Riverside typically run $80,000 to $150,000, making it the most budget-friendly ADU option.
Working Within Existing Walls
Because a JADU stays inside the home’s current footprint, you avoid foundation and heavy structural work. The bulk of the budget goes to the small kitchen, the separate entrance, sound insulation, and any electrical panel upgrades. We provide a written scope that separates required work from optional upgrades.
Owner-Occupancy Rules
Riverside follows California state law on JADUs, which means the property owner must live in either the main house or the JADU. We explain this rule before you spend money on plans, so you know exactly what you’re committing to.
ADU Plans
ADU Plans are the architectural drawings, structural calculations, and permit documents required to get your project approved by the City of Riverside’s planning and building departments. They’re the difference between a project that sails through review and one that sits in plan check for six months. Lodgewick ADU Riverside prepares full plan sets – site plan, floor plan, elevations, structural engineering, and Title 24 energy calculations – as part of every build. Plan fees in Riverside typically run $8,000 to $20,000 depending on the unit’s complexity, and we include that cost in your written proposal.
What the City of Riverside Reviews
Plan check covers setbacks, height limits, fire sprinkler requirements, and utility connections. Riverside also requires a soils report for most hillside parcels. We submit a complete package the first time, because resubmittal fees and delays are avoidable when the plans are done right.
Design That Matches Your Lot
Every lot is different, and a plan that works in Canyon Crest may not work in La Sierra or in nearby communities served by our ADU Builders in Mira Loma. We draw to your parcel’s actual conditions – slopes, easements, tree protection zones – not a template. For prefab units from Dvele or Mighty Buildings, we coordinate with the manufacturer to ensure the site plan matches the module specs.
ADU Contractor
An ADU Contractor is the licensed general contractor who manages the entire build – permits, subcontractors, inspections, and the final certificate of occupancy. You need one who carries the license, insurance, and the willingness to put the price in writing before work starts. Lodgewick ADU Riverside is that contractor. We’ve been building under The Kingswell Guarantee since 2010, and every project includes a written price, a defined arrival window, a clean job site, and a written guarantee. We never ask a homeowner to sign a contract with an open-ended estimate.
Why Written Pricing Matters
Contractor horror stories almost always start with a low verbal estimate and a change order later. We give you the full price before you commit, in writing, with line items. If something changes, the change order is written, signed, and agreed to before the work happens – not after.
Who’s on Your Property
Every Lodgewick ADU Riverside crew member is background-checked and wears a uniform with the Lodgewick name. You’ll always know who’s in your backyard and why. If you have a question mid-build, a live person answers our phone 24/7 – not a voicemail, not a chatbot.
ADU Design
ADU Design is the creative and functional planning of your unit – layout, natural light, storage, kitchen placement, and how the space connects to your backyard. Good design makes a 600-square-foot unit feel like 900, and it’s the difference between a rental that sits vacant and one that rents for top dollar. Lodgewick ADU Riverside designs units around how real people live: kitchen flow, closet depth, window placement for cross-breeze, and a separate entrance that doesn’t feel like an afterthought. Design fees are included in your plan set, and you’ll review every drawing before it goes to the city.
Space That Works Hard
We favor open floor plans with a defined sleeping area, a full bath with a real vanity, and a kitchen with full-size appliances where the lot allows. Built-in storage and tall ceilings make a small footprint live larger. In Riverside’s climate, we also design for shade on west-facing walls to keep cooling costs down.
Materials That Last
We specify James Hardie siding on most Riverside ADUs because it holds up to dry heat and resists termites. For prefab builds, we work with manufacturers like Abodu and Cover whose factory finishes are consistent and durable. You’ll see the material list and cost for each option before you choose.
Backyard ADU
A Backyard ADU is any accessory unit built in the rear yard of your property – detached from the main house and often paired with a small patio or garden space. It’s the fastest path to rental income in Riverside, where ADU-friendly zoning and strong tenant demand make backyard units a solid investment. Lodgewick ADU Riverside builds backyard ADUs that respect your existing outdoor space – we don’t pave over the whole yard to squeeze in a unit. Backyard ADU construction in Riverside typically runs $180,000 to $380,000 depending on size, utility distance, and finish level.
Placement and Privacy
We site the unit to maximize both your privacy and the tenant’s – separate walkways, thoughtful window placement, and a private entrance that doesn’t cut through your main living area. On smaller lots, we use vertical design and a compact footprint to keep usable yard space intact.
Utility Connections and Site Work
The distance from your main house to the backyard unit drives a big part of the cost – trenching for water, sewer, and power. We include those runs in your written estimate, so there are no surprises when the trenching starts.
Brands We Service
We work with leading prefab ADU manufacturers and materials suppliers because factory-built components often mean tighter tolerances and faster builds. We have hands-on experience with Abodu and Cover units, and we’ve built with Dvele’s high-performance panels. James Hardie siding is our standard exterior finish on custom Riverside ADUs because it stands up to the Inland Empire’s heat and dry conditions better than most materials.
Our team coordinates directly with the manufacturer on every prefab project – foundation specs, utility stub locations, and final finish work. Whether you have a specific brand in mind or want us to match the right system to your lot, budget, and timeline, we’ll lay out the options with real numbers attached.
Signs You Need a Pro Right Now
- Your permit application was rejected. Riverside’s plan check process is specific about setbacks, fire sprinklers, and utility connections. If your application came back marked up, you need someone who can correct the plans and resubmit without starting the clock over.
- Your lot has a slope or drainage issue. Hillside parcels in Riverside require extra engineering and drainage planning. Ignoring the slope means water against your foundation and a unit that fails inspection.
- You want rental income but you’re not sure the numbers work. A good ADU contractor will show you real construction costs and realistic rent projections before you commit. If someone’s giving you a verbal ballpark and pushing you to sign, walk away.
- Your existing garage has structural problems. Converting a garage with a cracked slab or termite damage is a repair job first and a conversion second. We inspect before we plan, and we’ll tell you if the garage is worth converting at all.
- A previous contractor walked off the job. Unfinished ADU projects are common, and they’re expensive to correct. We’ll assess what’s there, what’s salvageable, and what it’ll cost to finish it right – in writing.
Our Process, Step by Step
- 1
Free on-site consultation. We walk your Riverside property, measure the lot, check utility locations, and talk about your goals – rental income, family space, or resale value. You’ll get straight answers about what’s possible and what it’ll cost.
- 2
Written price and scope. Before you commit to anything, you receive a written proposal with line-item pricing, a defined arrival window for each phase, and the Kingswell Guarantee attached. No open-ended estimates, no verbal promises.
- 3
Plans and permits. We prepare full architectural plans, structural calculations, and Title 24 documents, then submit to the City of Riverside. We handle plan check comments and corrections until the permit is issued.
- 4
Construction. Our background-checked crew builds to the approved plan – foundation through finishes – with a clean job site at the end of every day. You get regular updates, and a live person answers the phone 24/7 if you have questions.
- 5
Final inspection and the 365-Day Done Right Promise. We walk the finished unit with you, pass the city’s final inspection, and hand you the written guarantee. If anything isn’t done right within 365 days, we come back and make it right – free.
How Much Does ADU Builders Cost in Riverside?
A typical ADU in Riverside runs $180,000 to $450,000 depending on the type, size, site conditions, and finish level. Here’s how the numbers break down:
- JADU conversion: $80,000 to $150,000
- Garage conversion: $120,000 to $200,000
- Detached prefab (Abodu, Cover): $180,000 to $300,000
- Custom detached ADU: $250,000 to $450,000
- ADU plans only: $8,000 to $20,000
What moves the price? Site distance from utilities, slope and soil conditions, the age of your electrical panel, and your finish selections. The best way to avoid overpaying is to get a written line-item estimate that separates required work from upgrades, and to ask what’s included. Every Lodgewick ADU Riverside estimate is free, written, and includes all permit fees, plan fees, and construction costs – no surprises at the end. Call (831) 292-4191 for an exact quote on your specific Riverside property.
Our Service Area Near Riverside
Lodgewick ADU Riverside builds across Riverside County and the western Inland Empire. We serve Riverside, Ontario, Fontana, plus Chino, Rialto, Upland, Montclair, Highland, Beaumont, Wildomar, Temescal Valley, and El Cerrito. For a free site visit and written estimate, call (831) 292-4191 – a live person answers, day or night.
Serving Riverside, CA - Our Local Coverage Area
We’re based in the Riverside area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
Frequently Asked Questions About ADU Builders in Riverside
An ADU builder is a licensed general contractor who specializes in designing, permitting, and constructing accessory dwelling units – secondary living spaces on the same lot as a main house. In Riverside, that includes detached backyard units, garage conversions, and JADUs. Call (831) 292-4191 for a free consultation on what’s possible for your property.
A JADU or garage conversion typically takes 4 to 7 months from plans to final inspection, while a custom detached ADU can take 8 to 14 months depending on size and site conditions. Riverside’s plan check process adds time to every project. We include a written timeline with every proposal so you know exactly what to expect.
ADU costs in Riverside range from $80,000 for a small JADU to $450,000 for a custom detached unit with premium finishes. Your specific number depends on lot conditions, utility runs, and finish level. We provide written pricing before any work starts – call (831) 292-4191 for a free estimate.
Yes, we have hands-on experience with Abodu, Cover, Dvele, and Mighty Buildings. We coordinate directly with the manufacturer on foundation specs, utility stubs, and site preparation. We’ll help you decide if prefab or custom is the better value for your Riverside lot.
If your existing ADU has a problem – water intrusion, electrical failure, or a structural concern – call us any time. A live person answers 24/7, not a voicemail. We’ll schedule a site visit and give you a written price before any repair work starts.
Our written guarantee covers workmanship and materials for 365 days after project completion. If anything we built isn’t done right, we come back and make it right – free of charge. That promise is in writing on every project, not spoken in a sales pitch.
Have your property’s parcel number handy if possible, and think about how you want to use the unit – rental, family, or resale. We’ll handle the measuring, zoning checks, and utility assessment. The consultation costs nothing, and you’ll walk away with real numbers either way.
Schedule Your ADU Builders Service in Riverside Today
Getting a straight answer about your ADU project shouldn’t mean chasing a contractor for weeks. Call (831) 292-4191 and you’ll reach a live person who can schedule your free on-site consultation. Russ Delmar and the Lodgewick ADU Riverside team will give you a written price, a written timeline, and the Kingswell Guarantee on every project. The estimate is free, the advice is honest, and the price never changes at the door.
Written by Russ Delmar, Owner at Lodgewick ADU Riverside, serving Riverside since 2010.
